Method of making strip sheets



- Patented Apr. 28, 1925.

*UNITED STATES" PATENT OFFICE;

and

them of t Drawing. I

I. N A'UGIIE AND ARTHUR J. TOWNSEND, OI" CANTON, I METHOD OF MAKING STRIP SHEETS.

To all whom it may concern.

Be it known that we, HARRY M. NAUGLE J. Townsmm, citizens 'of the United States, residing at coun of Stark and State of Ohio, have invente a new and useful Improved Method of M g Strip Sheets, of which the following is a s ification.

e The inventlon relates to the production of metal strip sheets, for use in making deep drawn or formed products; and the object of the improvement is to give the sheets the necessary high ductility required for the awing or forming operations, by a simple, direct, efi'ective and economical method. It is desirable, if not necessary, to make such stri sheets from an ordinary strip, skelp or ar, by a longitudinal rolling operatlon. A hot rolling reductiondoes not produce the necessary or desirable quality, surface, or accuracy to gauge; while a cold rolling operation has heretofore only been used to reduce the material to about onethird of itsoriginal thickness, without an intermediate anne lin The present method 'involves the production of a strip sheet having high ductility as well asthe desired. quality, surface an accuracy to gauge, for the pu intended, by first reducing the material rapidly, b a small number of bee drafts or passesbetw'een cold rolls, to say l ialf or less than half metal, followed by a quick annealing of the individual stri sheets which h rapidly reduced by the cold rolling operation. Y

A read 'ustment of the grains to relieve e strains produced by the rapid cold rolling reduction, cannot be accomplished by the ordinary box annealing of a.

mass oftmaterial, for the reasonv that the long period of heat the inner portions of the mass, not only results in an over-annealing of the outer rtion thereof, but in the roduction'fio a grain growth in a considerable portion of the mass, which destroys the duotility, and the uniformity, and also decreases the strength time required to properly 'outer portion of the charge.

4 open or a continuous method of quickly Inn individual sheets, however, not only prevents a growth of the but accomplishes a readjustment of 5: grains into a uniform structure with Application filed August 22, 1922. Serial so. 588,812.

Canton, in the -ness, and that bars run than theori inal thickness by ofthe original thiclmess of the b ave been f of the materialjin the b omom strip sheet the necessary high ductility, in addition to the desired 'quallty, accuracy of gauge, which has been v given to them by the cold rolling reduction. The best results have been obtained by an open annealing of individual sheets at a temperature of from 1200 to 1400 F, preferably 1300 F., in a cycle of fortyminutes or less. When, however, a very' thin strip is annealed bypassing it continuously through a heating tube-or tunnel, a much higher HEISSUED fine grains throughout, and gives to the.

surface and temperature may be employed and the time may be shortened to as lowa's a cycle of five minutes.

It will be understood that steel stri pa are usually one-fourth of an inch or un er in thickness, that skel runs from one-sixteenth to three-eight s of an inch in thickfrom one-fourth of an inch and u ward in thickness; and it has been found that the same canbe reduced to from fifty to sixty plea cent less m four to ten passes tween cold rolls, dependin upon the original thickness of the materia We claim: 1. The method of making I from a strip, skelp, bar or the like, which consists in rapid] reducing cold material to a strip sheet 0 less than half the original thickness, and then annealing the same y a continuous method. 4 v 2. The method of making a strip sheet,

a strip sheet rom a strip, skelp, bar or the like, which consists in rapid] reducing cold material to a strip sheet 0 less than half the original thickness, and then annealing the same in a short cycle'. 4

3'. The method of making a strip sheet from a strip,'skelp, bar orthe like, which consists in -rapidly-red ucing cold material to a strip sheet of lessthan half the original thickness, and tem 4. The method 'of making a strip sheet from a strip, skelp, bar or the like, which consists in rapidly reducing the material y a small number of heavy drafts between cold rblls to a strip sheet of'less than half the otiginal thickness, and then' annealing the slieetby a continuous method.

HARRY M. ravens I ARTHUR J. TOWNSEND.

"then annealing thesameat a rature of about 1300 F. in a short 

